SOLVED. What's the likely cause (and fix) for this window mould please?

ninjaef

Grand kids room.
Shocked when I went in. Not been in the bedroom for about a year.
My Daughter "didn't want to trouble me" . RRRRRR
This is her home, not rented, and would anyone be able to help please with advice.

couriervanman

Nothing major lack of ventilation
Give the window frames a good wipe down with a bleach cleaner/old toothbrush and open the window in morning to get rid of the condensation

Jeepers_Creepers

That's 'normal' condensation, the same as in countless other houses across the country (tho' - cough - most folk would have cleaned it up and wiped away the droplets before now...).

These are the coldest parts of the room, and in probably a cooler room than the rest of the house.

You basically either need to heat that room up to the point where that water goes back in to the air from whence it came - so probably a good 22oC plus, which is obviously nuts - or else you need to ventilate the room so that this moisture is removed naturally. This will, of course, make the room colder.

Then there's other stuff your daughter should be ensuring during these colder months - ways of reducing the moisture content in her house. So, don't dry clothes indoors (unless in a vented T/D), make sure you 'extract' when cooking, make sure you ditto when showering/bathing, etc.

Is this room used by your grandkids during the day, or are they lucky enough to be able to go to school? If the former, then you simply wipe that damp away with a paper towel first thing in the morning and keep the room at a temp the kids find comfy - 20oC-ish. If the room is not being used during the day, then simply wipe away that damp as before and then open at least two windows on to 'vent' setting and keep the bedroom door shut. Keep the temp low in there - no need for heat at all, in fact.

To get to a good starting point, clean away most of that black mould using a normal household cleaner and a toothbrush or similar, wipe it dry and then spray it with a mould killer/bleach - something like 'Astonish' which is cheap but effective (keep kids away when using this). Leave it for a good hour, and then wipe it clean with a damp cloth. That should get most of that discolouration sorted, but you can always apply more if needed - with the same safety proviso.

I suspect the condensation is worse in the mornings? Reasons for this include - the room temp is lower overnight so the air cannot hold as much moisture; it instead condenses out on the coldest surfaces. The windows are shut tight as is the door, so no air circulating and able to lift that moisture away. And sleeping bodies still release a fair bit of moisture which has to go somewhere.

If your grandkids could bear it (and this is why t'lawd gave us duvets), having the windows cracked open to 'vent' setting overnight would make a huge difference. Yes, the bedroom will be colder as a result, but bedrooms should be :-)   The heating will come on in the morning to take the chill off the air, and the first thing your g'kids do will be to jump out of bed and close the windows.

At the very least, you/your daughter should scrub these areas clean, and then apply mould killer - get it all fresh. Wipe away the 'killer afterwards. Then start a daily routine of:

(1) mopping up/wiping away all the condensation first thing each morning.

(2) if the room won't be used during the day, then crack open at least 2 windows to 'vent' setting, and shut the bedroom door - and keep the heat in there either low or completely off. It'll be as dry as a bone in there.

(3) If the room is being used during the day, then you'll likely want to keep the windows shut for warmth, so turn the heating to a comfy level - ~20oC - and leave the door open if possible to allow air to circulate.

(4) If you/your daughter/your g'kids can bear it, have two windows on 'vent' setting overnight, and the heating very low or off - this will make a huge difference to how much condensation you'll find in the morning, but it's understandable if you don't wish to do this - so just wipe it all up first thing every single morning instead and try and ventilate it during the day.

neilmcl

It's a common thing, just purely down to cold windows and lack of ventilation causing condensation , then mould. It can happen to pretty much anyone with even the best double glazing. As mentioned above just try and keep on top of keeping the area clean and occasionally spraying down with a decent anti-mould spray.

coffeehound

If there's any furniture located against exterior walls, it would be worth looking behind the furniture just to check there's no mould growing on the wall there too.

ninjaef

That you for replies. Heating is common feedback. The room is heated every day from 6am to 10pm. Room thermostats set to 19C. Lack of Heating cannot be the issue.

However, condensation, they dry clothes on rads. I've been telling them for years that they need to stop. I even bought them a dryer but they don't use it because of bills.. at least that's the reply i receive.

back to the mould...
Cleaned it many many times with bleach, mould spray, tea tree oil. keeps coming back. If i take the trim around the sill at the bottom, what do i use to stick it back on? there's something strong holding it together.

ninjaef

@Jeepers_Creepers I really appreciate your detailed reply👌 It does get cleaned and the room is heated and doors open and window open in the day when not raining.
On another forum, a member advised me to remove the trim and check gaps around the edge to see if rain or air is getting in. Going to do that later.

rach_k

It will keep coming back if the window is getting damp from condensation.  How often are they cleaning it?  It's not a case of wipe it down and ignore it until it's mouldy again, they just need to wipe up the water every day.  It's really nothing shocking or terrible, and, honestly, it doesn't seem like your daughter is that bothered either.  If my parent was telling me what I needed to do with my own home and how to dry my clothes, I might not reply very politely!  If she prefers to dry clothes on the radiator and deal with a bit of mould, that's her choice.

neilmcl

ninjaef said:

That you for replies. Heating is common feedback. The room is heated every day from 6am to 10pm. Room thermostats set to 19C. Lack of Heating cannot be the issue.

However, condensation, they dry clothes on rads. I've been telling them for years that they need to stop. I even bought them a dryer but they don't use it because of bills.. at least that's the reply i receive.

back to the mould...
Cleaned it many many times with bleach, mould spray, tea tree oil. keeps coming back. If i take the trim around the sill at the bottom, what do i use to stick it back on? there's something strong holding it together.

If it's not done regularly then it will keep returning especially if your daughter keeps introducing moisture into the room without adequate ventilation by hanging clothes on the radiators. You said it was the first time you'd seen it in a year so it can't be that often it gets cleaned. No point removing the window strip as this won't help you.

 Even with the room constantly heated, and tbh keeping it at 19C overnight is a real waste of money, you're still going to get cold areas around the window with the curtains/blinds closed and this will inevitably lead to condensation on the windows in the morning.

cattie

Perhaps a dehumifier would be a help, especially is clothes are being dried on radiators. It'd certainly remove some of the moisture that causes the mould growth.

Jeepers_Creepers

ninjaef said:

@Jeepers_Creepers I really appreciate your detailed reply👌 It does get cleaned and the room is heated and doors open and window open in the day when not raining.
On another forum, a member advised me to remove the trim and check gaps around the edge to see if rain or air is getting in. Going to do that later.

There's no rain getting in. Really, this is as typical a case of condensation as could be.

That room is heated during the day AND has its windows open at the same time? That's insane - simply a waste of energy.

Is the room USED during the day? If so, then - yes - keep the heat on because you need to. If not, then shut the door, turn the heat down in that room and open the windows as much as you can until the room is required again. When you go in to that room, it'll be chilly - but dry. Close the windows when you need to, and turn the heat back up.

I'm assuming that the condensation shown in your pic is typical for the mornings but doesn't reappear as badly as that after it's been thoroughly mopped up first thing and the room vented? If it does keep reappearing that badly during the day, then it's down to what you suspect - the drying of clothes in the house. We are probably talking about litres of water in total, and that has to go somewhere.

3 places it can go; one is that it's held in the air because the air is warm enough to hold it, but if that air isn't vented away, it will condense out at some point, usually overnight when the temp drops. Another place - the correct place - is to ventilate it away, but this means cracked-open windows. The other place it goes is... where you see it - as droplets on the window!

This is about constant management during Winter months. Mop up totally using paper towels, and give it a spray of mould killer (eg Astonish Mould & Mildew Blaster) - this will kill the spores and bleach the stains. Do this regularly and you'll get that back to white. If the mastic/sealant/silicone looks ropey even after it's had a thorough 'Blasting', then you could run a bead of a good quality silicone sealant over it, finishing it off with a rubber tool. Ideally you'd remove the existing stuff first, but it actually looks ok to me, and has enough space for a clean new bead applied over it; the original needs to be thoroughly clean first, tho'. (Your call - best to redo, but a lot more work).

Sorry - the level of black mould on that surface shows quite simply that it is not being cleaned up regularly, not even once a week.

Dry it - scrub it clean - apply killer. Leave for an hour. Wipe clean. Keep it clean...